Please note: if you use wired ethernet eth0, you should do something like this:

sudo sysctl net.ipv6.conf.eth0.accept_dad=0

It is unclear to me where the problem is: in Linux itself , or in my modem, or in the interaction between Linux and my modem.
The problem also occurs in OpenSuSE 12.2 on the same LAN, so it's not a Ubuntu-only problem.

4 comments:

JMM
said...

Hello. I did not use the dad=0 setting as in your post. But the link to the launchpad bug then the workaround : net.ipv6.conf.eth0.use_tempaddr=-1 worked for me for a while but still I keep receiving the annoying ipv6 dupe from dmesg. Looking around more I was able to find an interesting topic about 802.11n data when being transmitted and received at my end Intel Centrino N 6250 disconnects wifi (iwlwifi) then the issue would resume. The zorin folks mentioned to disable N-data. More here. And it seems to work. You will still some messages but it would stop at some point completely.